Discharge tube



y 1939. w. ESPE DISCHARGE TUBE Filed July :5 1936 INVENfOR n. ESPE Maw 06M ATTORNEY Patented July 4, 1339 UNITED STATES PATENT OFFICE} DISCHARGE TUBE I Werner Espe, Siemensstadt, Berlin, Germany, as-

signor to Siemens and Hals ke Aktiengesellschaft, Siemensstadt, near Berlin, Germany, a

German company Application July 3, 1936, Serial No. 88,757 v ;In Germany September 19, 1935 9 Claims. (01. 250-275) Discharge tubes have already been; manuiac tured whose walls consist wholly or partially of ceramic materials. The presentinvention relates to improvements in such discharge tubes.

In accordance with the invention' in-an electrical discharge tube whose walls consist at least partially of ceramic materialathe walls are provided with window-type apertures in which the electrodes are set, for example soldered in. It

;l() is thereby immaterialwhether the window-type apertures-serving to receivethe electrodes are provided on the front or side walls of the tube. It is recommended to employ as ceramic materials for tubes in accordance with the invention those materials having a low angle of loss and. a high vacuum density, for example calite or calan. Quartz would also be suitable for this purpose.

Experience has .shown that it frequently happens that with movable and transportable apparatus in which electrical discharge tubes are employed, the latter get loose or fall out of their sockets. Soldering, however, is unsuitable, particularly because the rapid interchangeability of the discharge tubes thereby becomes impossible. Therefore bayonet valve sockets have already been suggested whose lateral surfaces are provided with individual pinsserving for contact making and for leading into the appurtenant bayonet socket. With discharge tubes in accordance with the present invention such pins can easily be arranged on the lateral limiting surfaces of the tube whereby they are adapted for insertion in bayonet sockets.

The invention will be clear from the drawing. Figs. l-, 2, 2a, 3 to 5, 5a, 6 and 7 show some examples, that is Fig. 1 shows a single anode rectifier whose portion l is made of a ceramic material. 2 is the cathode whose lead wires enter the tube at the points 3 and 4'. 5 is the anode which is connected in the window-type aperture at 6 with the ceramic portion I in accordance with one of the well-known methods of soldering.

Figs. 2 and 2a. show an example of a threeanode rectifier in which the anodes l and 8 and the third anode not shown in Fig. 2 of the drawing are inserted in the window-type apertures which are situated in the jacket surface of thecylindrical vessel. ID are window-type metal portions through which the lead wires to the 5 cathode enter the tube. I l is a bridge of ceramic material for the purpose of giving the front of the tube greater stability and insulating the windows ID from each other. The front of such a discharge tube can also be constructed convexly I 55 as shown in Fig. 3 in. order to increase the se- .tected against falling out.

In Fig. 5 the anodes 1, 8 and 9 are constructed concave. Thereby the advantage is obtained that the ceramic parts of the wall for thermionic reasons are further away from the hot cathode than ;l thegmetal anodes which on account of the discharge conditions must be arranged as near as possible to the cathode. l3 represents metallic screens which serve for screening the insulating surfaces against the rebounding electrons and to 20 prevent secondary emission. Such a metallic screening of the ceramic walls can also be obtained by metallizing the ceramic walls with a metallic coating 16, as shown in Fig. 5a. in accordance with one of the known methods and by 25 grinding out suitable portions, taking care that a conductive connection no longer exists between c this metal coating and the electrodes, for example the anodes.

With examples according to Fig. 5 an intensive 80 cooling of the anodes I, 8 and 9 can also very easily be obtained by surrounding the discharge vessel for example with 'a cylindrical sheath l4 and then moving a gaseous or fluid cooling means along the anodes. 35

In Fig. 6 by a corresponding construction of the anodes I and 8 their cooling is taken care of. The anodes can either be made corrugated or provided with cooling ribs.

Fig. 7 shows an example of a discharge tube 4 according to the invention which in addition to the anodes and the cathode has a further grid type electrode l5, for example in the middle, which may beemployed for example to control the discharge tube. 45

The inventive idea is not exhausted by the embodiments shown. A series of other embodiments are conceivable in accordance with the invention in which oneor more electrodes of the discharge tube are inserted in window-type apertures of the ceramic walls.

What is claimed is:

1.,An electron discharge device comprising a hollow enclosing vessel of ceramic material having apertures in one end thereof, metallic plate wall of said vessel, and terminals projecting from some of said members.

3. An electron discharge device comprising an.

enclosing vessel of ceramic material having apertures formed in the side walls thereof-,- and riietal lic members sealed within said apertures. and

preserving the contour of said vessel.

4. An electron discharge device comprising an enclosing vessel of ceramic material-having ape'r; tures quadrilateral formed in the side walls th'ereof, and electrodes sealed in said apertures flush with the surface of said vessel.

5. An electron dischargedevice comprising a cylindrical enclosing vessel'of ceramic material having a window-type aperture'th-erein, a metallic electrode sealed in said apertureflush: with the exterior wall of said vessel, an electron emitter within said vessel, and terminals for said emitter sealed in the Wall of said vessel. 6. An electron discharge device including an envelope of ceramic material; said envelope having a slot extending through its wall -andagroove on a surface of the envelopesuperimposed-on said slot, a thermionic cathode within said: envelope, and another electrode supported in" said groove and sealed to said envelope and closing said slot. v

7. An electron discharge device including an envelope of ceramic material, said envelope having a plurality of slots extending through the wall thereof, an electrode positioned in the wall of and sealed to said envelope and closing one of said slots, a thermionic cathode within said envelope; and'ganother electrode supported in the wall ofsaid envelope in register with another of said slots and out of contact with said first mentioned electrode.

8 electron discharge device including an envelope of ceramic material having a plurality 'f-' lots" extending; through the wall thereof, a

said envelope superimposed on each id sly s, an electrode constituting a part of "surface of said envelope positioned in :azzgroofveiand "hermetically sealed to said en- -=v1ope-=ovr=ohe of said slots, and another elecfirst-mentioned electrode."

An'felectrqn dis'char'ge'fdevice' including an 'envelop'e' o fjceramic material having slots extending through the wall thereof, a metallic electrode in the 'wall vof said envelope and hermetically ,Siiled .to sai'd'envelope over atleast one of said 7 athermionic cathodewithin said envelope, thewvall of saidgenvelopebeing provided with a groove on a surfaceof-the envelope and super- ;imposed'onyat-least 'oneoi said slots, and an- .other electrode supported in said groove out of contact with the first-mentioned electrode.

WERNER EsPE. 

